Means for adjusting electrical contacts



July 59 @9231 L. L. N ETT LETON MEANS FOR ADJUSTING ELECTRICAL CONTACTS Filed Oct. 21, l925 INVENTOR.

Patented July 5, 1927.

LEWTS I1. NETTLETON,

OF EDGEWOOD BOROUGH, ?ENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SVJ'ISSVALE, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

MEANS FOR ADJUSTING ELECTRICAL CONTACTS.

- Application filed October 21, 1826. Serial No. 143,217.

My invention relates to adjusting means for electrical contacts, and has for an object the provision of means for accurately adjusting the position and the pressure of a contact member. The invention is particularly adapted for, though in no way limited to, adjusting means for the fixed contact elements of a vibration relay.

1 will describe one form of adjusting means embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a sectional view showing one form of contact member and adjusting means therefor embodying my invention.

Referring to the drawing, the reference character 1 designates a supporting block which carries a contact assembly comprising a relatively stifi' spring 7 and a relatively flexible contact finger 8 provided with a contact tip 9. The finger 8 is attached to the spring 7 by rivets 11, and the entire assembly is fixed to the supporting block 1 by a screw 6. The contact finger 8 normally rests against the inwardly bent free end 13 of the spring 7, and the tip 9 is arranged to be engaged by another contact member which is not shown in the drawing.

The block 1 is provided with a threaded hole which receives an adjusting screw 2 the inner end of which engages the flexible contact linger 8. The screw 2 is provided with a longitudinal threaded hole which receives a second adjusting screw 3, and the end 12 of this screw passes through a hole 10 in the spring 8 and engages the stiff contact spring 7 By turning the screw 3 it will be seen that the position oi the contact tip 9 may be varied, whereas by turning the screw 2 it will be seen that the pressure of the contact finger 8 against the spring 7 may be varied. Lock nuts 4 and 5 are preferably provided on the screws 3 and 2, respectively, to retain these screws in position after adjustmcnts are made.

The screws 2 and 3 preferably have threads of the same pitch, so that it screw 3 is held while screw 2 is turned, the position of the contact tip 9 will not be changed but the pressure of the finger 8 on the end 13 of spring 7 will be varied.

It is, of course, understood that the contact tip 9 co-acts with a movable contact member and that the engagement of the two members tends to move the tip 9 to the right away from the toe 13.

Although I have herein shown and described only one form of adjusting means embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a supporting member, a relatively stifl? spring attached to said member, a relatively flexible contact finger attached to said spring, a screw passing through said member and co-acting with said finger to adjust the pressure of the finger against said spring, and a second screw passing through a longitudinal threaded hole in said first screw and through a hole in said finger and co-acting with said spring to adjust the normal position of the finger with respect to said supporting member.

2.111 combination, a supporting member, 7

with respect to said supporting member, the

pitches of the threads on said screws being the same so that the inner screw may be held stationary and the outer screw may be turned to adjust the contact pressure Without disturbing the adjusted position of the contact finger.

In testimony whereof I affix my signature.

LEWIS L. NETTLETON. 

